# Energy conversion: two interphases

**URL:** https://discourse.obspy.org/t/energy-conversion-two-interphases/1711
**Category:** Related: rf
**Created:** [May 19, 2023, 8:04am UTC](https://discourse.obspy.org/t/energy-conversion-two-interphases/1711 "2023-05-19T08:04:09Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Qian](https://discourse.obspy.org/letter_avatar_proxy/v4/letter/q/b782af/32.png) [@Qian](https://discourse.obspy.org/u/Qian)
#### Post date: [May 19, 2023, 8:04am UTC](https://discourse.obspy.org/t/energy-conversion-two-interphases/1711/1 "2023-05-19T08:04:09Z")

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![Conversions](https://discourse.obspy.org/uploads/default/original/1X/6a678cd87e5a9accb441c723344d1f44fac0ff97.png)

Hi Tom! I have a theoretical question. I sketched the situation in the attached plot. With my data, I am able to reproduce the sketched situation, which was expected.  
Where we expect double signals is where I have the confusion  
My doubt is:  
What is really happening there? the P rays convert at the converter 1 and then the S converted rays just ignore the shallowest converted? Would be the deeper interface (lithosphere 1 in the sketch) the only one that generate mode conversion? Or are there conversions in the deeper converter and then also in the shallowest one?  
Thanks in advance!

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### Author: ![trichter](https://discourse.obspy.org/user_avatar/discourse.obspy.org/trichter/32/226_2.png) [@trichter](https://discourse.obspy.org/u/trichter)
#### Post date: [May 22, 2023, 9:43am UTC](https://discourse.obspy.org/t/energy-conversion-two-interphases/1711/2 "2023-05-22T09:43:57Z")

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Hi Qian, with two or more interfaces it is of course more complicated. Apart from the single conversions you will get a mixture of multiply converted (and reflected) waves. There will be conversions at every interface. The dipping adds more complexities, probably you will see a signal on the T transverse component.